Field of the Invention
The present invention relates to a drag adjustment knob. More specifically, the present invention relates to a drag adjustment knob for a spinning reel that adjusts the drag force of a drag mechanism that brakes a spool rotatably mounted on a spool shaft, the spool shaft being movable forward and backward with respect to a reel unit of the spinning reel and having a first screw on its front end, the spool being rotatably mounted to the spool shaft while being restricted from moving rearward.
One type of conventional drag adjustment knob that adjusts the drag force of a front drag mechanism provided on a spool of a spinning reel includes a first adjustment unit that sets the initial drag force, and a second adjustment unit that adjusts the drag force to be higher than the initial drag force (see, for example, Japanese Utility Model Application Publication No. H06-29032, FIGS. 8 and 10). The first adjustment unit is used to set the minimum initial drag force, e.g., the force at which the fishing line will not snap. The first adjustment unit is screwed onto a male screw formed at the front end of a spool shaft. The second adjustment unit includes an operating portion that is arranged outward in the radial direction of the first adjustment unit, and which screws onto a transmission member non-rotatably mounted on the spool shaft. Forward movement of the transmission member is restricted by the first adjustment unit. The second adjustment unit is in contact with the drag mechanism, and can set the drag force to be higher than the initial drag force. The screw pitch of both adjustment units is set to be the same or different.
In a conventional drag adjustment knob having this type of configuration, the initial load of the drag force is set by rotating the first adjustment unit. Then, with the initial drag force set, the drag force can be increased from the initial drag force by the second adjustment unit. This allows one to prevent a fish from escaping and the fishing line from breaking due to the drag force being set to a level lower than necessary.
With a conventional drag adjustment knob having the two aforementioned adjustment units, by increasing the screw pitch of the second adjustment unit so as to be larger than that of the first adjustment unit, the percentage increase in the drag force with respect to the amount of rotation of the second adjustment unit can enlarged, and thus the desired drag force can be quickly set. However, if the screw pitch is too large, the number of engaged screw threads will be reduced and the strength of the screw will be compromised. Because of this, with the aforementioned conventional configuration, there may be damage to the screws when a large drag force is set.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved drag adjustment knob for a spinning reel that overcomes the above-described problems. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.